Some people like having the best tools, whether they know how to use them to their best advantage or not. Some people can't afford the best tools and therefore must learn to make the tools they do have work efficiently, perhaps at the limit, and achieve the best results possible from those tools. Give those folks the best tools and see the limits expand for them. And then, some folks have no need of the best tools because they stay well within the envelope and always will. I like to think I belong to that second cohort, the efficient tool users. Last I counted, in my shop I have at least ten hammers, inherited, bought or purpose-made, each of which is reserved for a different job but none of which would be worth much to anyone else. In group three, above, hanging pictures is about as challenging as it gets for the household hammer.
As to cameras, if all one will ever do is post a down-sampled image to the web or print a 4x6 for the family album, you're nearly spot-on. OTOH, if you want to cover your wall with really good looking images, printing large will be a lot easier with a D600 or D800 or D7100 shot with good technique than with a 12-16 Mp P&S. Some of the capabilities of DSLRs make some images far easier to acquire (think differences in shutter lag, DOF, etc.). I'm pleased to be using a D600 and feel I can certainly tell the difference it makes in my images.
Different tools do different things but still the major discriminator will nearly always be the user. I read the same thought somewhere (I wish I could remember so as to give due credit) and better expressed, to wit, 95% of todays cameras are capable of taking publishable images - a capability not matched among their users.